There are some good points here comparing HTTP2 and SPDY, but I’m mostly linking to this because of the three wonderful opening paragraphs:
A very long time ago —in 1989 —Ronald Reagan was president, albeit only for the final 19½ days of his term. And before 1989 was over Taylor Swift had been born, and Andrei Sakharov and Samuel Beckett had died.
In the long run, the most memorable event of 1989 will probably be that Tim Berners-Lee hacked up the HTTP protocol and named the result the “World Wide Web.” (One remarkable property of this name is that the abbreviation “WWW” has twice as many syllables and takes longer to pronounce.)
Tim’s HTTP protocol ran on 10Mbit/s, Ethernet, and coax cables, and his computer was a NeXT Cube with a 25-MHz clock frequency. Twenty-six years later, my laptop CPU is a hundred times faster and has a thousand times as much RAM as Tim’s machine had, but the HTTP protocol is still the same.